Design of MEMS gyroscope for wide range resonance frequency adjustment

In this paper, we present a design and simulation results of MEMS gyroscope using drive and sense electrode's voltage control to tune wide range resonance frequency that may yield robust vibratory MEMS gyroscope and at the same time retains the wide range of bandwidth. The design is of symmetrical shape for the proofmass and the branch-finger actuators. Branchfinger actuators in both drive and sense's mode also acted as stiffness tuner. Flexure shapes, although not exactly symmetrical, give us equal spring's constant in both x- and y- directions resulting in a matching resonance frequency. By properly arranging the voltage of drive and sense electrodes, we can have distributed drive-mode resonance frequency to overcome the sense-mode response shift due to changes of system parameters (e.g: fabrication imperfection or operating conditions). The capacitance in the sensing direction is measured between the perforated proofmass and perforated electrode plate underneath. From the simulation results we found out that the maximum range of bandwidth for the design is 358 Hz. Although we only varies the beam length, the experiment had shown that the design can give alternative to control mode mismatch.